Currently, there exist a number of conventional systems for separating impurities from a feed solution. For example, ion exchange systems are configured with resins to extract impurities from a feed liquid such as groundwater and/or potable water. These impurities are accumulated until the ion exchange resin has been exhausted, namely all of the replacement ions coated on the resin are gone. Thereafter, the ion exchange resin must be either disposed of as a hazardous material or regenerated.
In order to regenerate the ion exchange resin, a large volume of brine solution is applied thereto. In most cases, the brine solution is an aqueous solution, perhaps with an elevated level of minerals, such as replacement ions for ion exchange resin regeneration.
During regeneration of the resin, the brine solution causes the impurities to be released. As a result, a large volume of brine solution, perhaps a thousand or more gallons of brine solution in some cases, is contaminated with the released impurities (hereinafter referred to as “contaminated brine solution”). Usually, the contaminated brine solution needs to be transported to an off-site waste treatment facility. Such removal of the contaminated brine solution poses a substantial cost.
Similarly, membrane separation systems are designed with a membrane to separate different ionic material from water. For example, nano-filtration uses a porous membrane that is partially permeable to perform such separation. The separated ionic materials are as part of the reject solution that is output along with the filtered water. Since the composition of the reject solution is substantially water, and only a small amount of separated ionic material, it is not cost effective to merely dispose of the reject solution.
Clearly, it would be advantageous from a cost standpoint to recycle the contaminated brine solution or reject solution as well as reduce the volume of materials that need to be treated as waste.